Swedish modular wall unit --similar to Cado  

Hello all, hope someone can help me out...I inherited a modular wall unit from my husband's grandparents. We cannot find the hardware that will hang the shelves from the wall-mounted wood strips. My hope is that if I can identify the manufacturer, I can at least find out what sort of hardware was used and maybe find similar at a store.
I laid the wall strips on my table and placed a shelf the way it used to hang. Also pictured is the "secretary" unit and close ups of the beveled holes the shelves/cabinets have. The cabinets--secretary and two book cases--also have a cut-out notch at the bottom, I imagine so that they have some support other than whatever hangs them from those holes.
I can find tons of Danish units on-line, but nothing from Sweden and nothing that is *quite the same.
Anyone? Thanks!
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